Device for forming a dough strand

ABSTRACT

Apparatus for forming a dough strand from a preferably large-volume dough mixture ( 28 ) has a receptacle ( 2 ) for holding this dough mixture, which is provided at the bottom With a discharge opening ( 4 ) for the dough. Connected to this discharge opening are two shafts ( 6 ) arranged so as to be parallel to one another and driven in opposite directions in order to effect a downward movement of the dough. The shafts ( 6 ) are provided with profiles acting on the dough which are formed by star arms ( 5 ). The shafts ( 6 ) are arranged so as to be fixed and are driven in a timed manner for the rotary movement. The star arms ( 5 ), of which there is an even number for each shaft ( 6 ), in the position directed towards one another block the downward flow of dough therethrough over the major part of the axial length of the shaft ( 6 ). The star arms ( 5 ) of each shaft ( 6 ) are, however, provided at the shaft ends alternately with cutouts ( 10 ) for the flow of the dough therethrough during the pauses in the timed rotary movement of the shafts ( 6 ). Underneath the shafts ( 6 ) are arranged two depositing belts ( 12 ) in the longitudinal direction of the shafts and spaced apart from one another, which belts are drivable for circulatory movement in opposite directions and for preferably joint reciprocal displacement in the longitudinal direction thereof.

[0001] The invention relates to an apparatus for forming a dough strandfrom a preferably large-volume dough mixture, comprising a receptaclefor holding the dough mixture, which is provided at the bottom with adischarge opening for the dough, to which two shafts are connected,arranged so as to be fixed parallel to one another and driven inopposite directions in a timed manner in order to effect a downwardmovement of the dough, the said shafts being provided with profilesacting on the dough in the form of an even number of star arms for eachshaft.

[0002] An apparatus of this kind is known from AT 283235 B.

[0003] In bakeries it is often necessary to form a dough strand from adough mixture. This dough mixture mostly has a large volume, dependenton the size of the kneader with which the dough mixture has beenprocessed. Usual large volumes are about 80 to 240 kg. In order to formdough strands of this kind, separating strips from the dough mixture bymeans of reciprocating cutters is known, the said strips being lined upone after another overlapping and thereby forming a continuous ribbon ofdough. However, this ribbon of dough does not have a uniform thicknessat the overlap points, so that subsequent processing is required,causing further undesirable demands to be made on the dough.

[0004] Extruding the dough through a nozzle is also known, the nozzlecross-section determining the cross-section of the strand of dough to beproduced. This procedure also has the disadvantage of considerabledemands being made on the dough.

[0005] Finally, forming a continuous ribbon of dough from a large volumeof dough by means of moving profiled roller pairs is known (EP 744 126B). Here too, however, considerable undesirable demands made on thedough result.

[0006] The object of the invention is to avoid considerable demands ofthis kind being made on the dough and to produce a dough strand with atleast approximately uniform thickness. Taking as starting point theknown design mentioned in the introduction, the invention achieves thisobject in that the star arms of the shafts in the position directedtowards one another block the downward flow of dough therethrough onlyover the major part of the axial length of the shafts, the said stararms of each shaft, however, being provided at the shaft endsalternately with cutouts for the flow of the dough therethrough duringpauses in the timed rotary movement of the shafts, and in that twodepositing belts are arranged underneath these shafts in thelongitudinal direction of the shafts and spaced apart from one another,which belts are drivable for circulatory movement in opposite directionsand for preferably joint reciprocal displacement in the longitudinaldirection thereof. In an apparatus of this kind, the star arms of thetwo shafts in the position directed towards one another hold back thedough over the majority of the length of the shafts. Only where the stararms are provided with cutouts is a gap formed through which the doughis able to flow, so that the connection to the volume of dough locatedin the receptacle is always maintained. If a step of the timed rotarymovement of the two shafts now occurs, a dough strand of the doughmixture located in the receptacle is separated by the following stararms and deposited downwardly onto the depositing belt located directlyunderneath the two shafts. This dough strand remains connected to thedough mixture in the receptacle since dough continues to flow throughthe newly opened gap formed by the cutouts of the star arms, onlypositioned at the other star shaft end, however, and this is implementedin such a way that it joins up with the deposited dough strand. Thedough strand deposited in the next rotating step-by-step action of theshafts joins up with the previously deposited dough strand length, andso on. The individual dough strand portions joined up together arrive onthe depositing belts. By means of the reciprocal movement of the saidbelts adapted to the timed rotary movement of the shafts, the as-it-weremeander-shape discharged form of the dough strand delivered by the starshaft pair is transformed into a continuous, linearly extending form ofthe dough strand, which may be supplied for further processing.According to a preferred embodiment of the invention, this isimplemented by means of a delivery belt arranged underneath the twodepositing belts and driven continuously for circulatory movement.

[0007] By appropriately matching the size of the cutouts to the shaftrotation, a largely uniform thickness of the dough strand produced mayeasily be achieved.

[0008] For constructional reasons it is expedient to arrange the twodepositing belts on the same level in such a way that they are spacedapart at their ends directed towards one another. This spacing forms alocation for the dough strand to pass through between the two depositingbelts to the delivery belt. This spacing is preferably at least the sizeof the thickness of the dough strand to be produced in order to avoidcompression of the dough strand between the two depositing belts.Furthermore, according to a preferred embodiment of the invention, thearrangement is such that each depositing belt is at least as long as themutual spacing apart (measured in the axial direction of the shafts) ofthe cutouts arranged at the two ends. As a result the dough strandportions supplied via the cutouts of the star arms to the depositingbelts easily join up with the dough strand portion deposited on thedepositing belt in the course of the rotary movement of the shafts.

[0009] The even number of star arms of each shaft is four, according toa preferred embodiment of the invention, which has the advantage that inthe position of a star arm pair directed towards one another andgenerally horizontal, in which position the said pair blocks the flow ofdough therethrough over the star arm length, the following star armsextend vertically upwards and as a result do not obstruct the follow-onflow of the dough to the opening formed by the particular cutout.

[0010] The cutouts of the star arms, according to a preferred embodimentof the invention, start from the edges of the star arms remote from theshaft axis. This is constructionally simpler than gaps in the star armsclose to the axis and moreover enables the cutouts of each of two stararms cooperating with one another to block the flow of doughtherethrough in the central region of the discharge opening of thereceptacle to be arranged such that these two cutouts in each case forma common opening whose size equals the sum of the two cutouts. Eachcutout is preferably rectangular and the individual cutouts are each thesame size to keep the timing times the same.

[0011] The two star arm shafts are expediently driven by a common motorto ensure the most synchronous movement possible. However, according tothe invention an individual motor may be provided for each depositingbelt for the circulatory movement, which can run simultaneously with thedepositing belt. The drive of the circulatory movement of the twodepositing belts may therefore be adjusted or regulated mutuallyindependently so that it is better able to adapt to the conditionsprevailing at the time. The two depositing belts are expediently held ina common frame which is movable to and fro by means of a drive in theaxial direction of the shafts. This ensures that the gap formed by theaforementioned spacing between the two depositing belts remainsconstant, but the arrangement may be made such that this gap width isadjustable.

[0012] Further characteristics and advantages of the invention areevident from the present description of an embodiment representedschematically in the drawing.

[0013]FIG. 1 shows the apparatus in a vertical section. FIG. 2 is asection along line 11-11. FIG. 3 shows in axonometric representation thetwo star shafts on a larger scale. FIG. 4 to 11 show the apparatus invarious operational phases in sections as in FIG. 1 and 2. FIG. 12 showsschematically the depositing of the individual portions of the doughstrand.

[0014] The apparatus has a support 1 which carries a receptacle 2 forholding the dough for processing. This receptacle 2 has a large volume,about 80 to 240 kg, so that it can hold the dough mixture 28 previouslyprocessed by a kneader in its entirety. The receptacle 2 has side walls3 arranged at an angle (FIG. 2), resulting in a funnel shape whosedischarge opening 4 is at the bottom. Connected to this dischargeopening 4 are two shafts 6 provided with star arms 5 and mounted in thesupport 1 such that, in the position of the two shafts 6 represented inFIG. 2, the dough outflow from the discharge opening 4 is closed off bymeans of two star arms 5, directed towards one another, over a majorpart of the axial length of the two shafts 6. The two shafts 6 aredriven together for circulatory movement in opposite directions (arrows7) in such a way that, as the two shafts 6 rotate, conveying of thedough downwardly out of the discharge opening 4 results. The two shafts6 are coupled by means of gears 8 (FIG. 1) wedged thereon such that theymay be driven by a single motor 9 for rotary movement, and this may takeplace in a timed or intermittent manner, i.e. with stationary phasesexisting between the individual movement steps, in which the two shafts6 adopt the position represented in FIG. 2 in which the discharge of thedough out of the discharge opening 4 is interrupted over the major partof the axial length of the shafts 6.

[0015] As FIG. 3 shows, each shaft 6 is provided with four star arms 5mutually staggered by equal angles, i.e. 90°. Each star arm 5 does notextend over the whole axial length of the shaft 6, however, but has onone end face of the star arm a cutout 10 which starts from the edge 11of the respective star arm 5 that lies parallel to the axis of the shaft6. Each cutout 10 is rectangular and the individual cutouts 10 arearranged on the star arms 5 of the relevant shaft 6 alternately suchthat a cutout 10 on the right-hand end face of the shaft 6 (with respectto the representation in FIG. 1) follows a cutout 10 on the left-handend face of the same shaft 6 when the shaft 6 is rotated in the arrowdirection 7 (FIG. 2). Further, the cutouts 10 are arranged on the twoshafts 6 such that two cutouts 10 in each case lie opposite one anotherwhen the star arms 5 reach the position according to FIG. 2. The twocutouts 10 of the two shafts 6 then form a common opening through whichthe dough is able to flow downwardly out of the receptacle 2.

[0016] The dough exiting downwardly out of the receptacle 2 through thedischarge opening 4 thereof arrives on the upper run 13 of one of twodepositing belts 12 arranged on the same level and arranged so as to bespaced apart horizontally from one another, thereby leaving a spacebetween the two ends of the two depositing belts 12 directed towards oneanother which forms a gap 14 that is at least as large as the thicknessof the dough strand to be produced. The two depositing belts 12 aredriven by means of respective motors 1 5, and this is implemented inmutually opposite circulatory directions (arrows 16). The two depositingbelts 12 are displaceable to and fro in the direction of the doublearrow 17 (FIG. 1), far enough for the gap 14 to arrive alternatelyunderneath one of the two openings formed by the cutouts 10. To thisend, the two depositing belts 12 are held in a common frame 18 which isonly schematically represented in FIG. 1 and is movable to and fro inthe double arrow direction 17 by means of a drive 19, e.g. apneumatically or hydraulically operated double-acting cylinder. Thisframe 18 is of course designed such that it does not obstruct thepassage of the dough strand through the gap 14. The two depositing belts12 may be so arranged in the frame 18 that the width of the gap 14 canbe varied to enable it to match different thicknesses of the doughstrand to be produced. Optionally, however, the two depositing belts 12may also be displaceable horizontally independently of one another, butprovided that the receiving, mentioned later on, of the dough strandflowing downwardly in a meander shape from the star arms 5 or thecutouts 10 thereof on the depositing belts 12 remains ensured.

[0017] The two depositing belts 12 together form a continuous doughstrand which may be supplied for further processing. Expediently, thisdoes not take place directly, instead the two depositing belts 12deposit the dough strand portions received by them onto a delivery belt20 arranged underneath the two depositing belts 12 formed by continuousbelts, the said delivery belt also being formed by a continuous belt.The delivery belt 20 is driven by means of a motor 21 for continuouscirculatory movement in the direction of the arrow 22 and supplies theproduced dough strand to further processing at location 23.

[0018] The apparatus operates as follows:

[0019] A position of the star arms 5 of the shafts 6 and the twodepositing belts 12 according to FIG. 4 and 5 is assumed. In thisposition the dough mixture 28 in the receptacle 2 is only able to flowout through the opening 26 located on the left in FIG. 4, which isformed by the two mutually facing cutouts 10 of the two star arms 5 ofthe shafts, which star arms 5 otherwise block the downward passage ofthe dough. A dough strand portion 24 is thereby produced, which arriveson the left-hand depositing belt 12 arranged underneath the two shafts6. As a result of the circulatory movement (arrow 16) of the said belt,the dough strand 24 deposited on the depositing belt 12 is continuouslysupplied to the gap 14 and through this gap 14 is deposited on the upperrun 25 of the delivery belt 20. At the same time the frame 18 containingthe two depositing belts 12 is displaced by means of its drive 19 to theleft (FIG. 4) so that the gap 14 gradually arrives in the positionaccording to FIG. 6. It is apparent that the delivery belt 20 has thenalready received part of the dough strand 24. While the two shafts 6with their star arms 5 are stationary, the frame 18 with the twodepositing belts 12 moves further to the left (FIG. 6) and finallyreaches the left-hand end position according to FIG. 8. As soon as thisposition is reached, the two shafts 6 are further rotated 90° in thearrow direction 7 (FIG. 2). This timed step-by-step action takes placeso quickly that a dough strand piece 24′ over the length of the stararms 5 is deposited during this star arm rotation onto a depositing belt12, but now onto the right-hand depositing belt 12 (FIG. 9). At the sametime the aforementioned further 90° rotation of the shafts 6 causes thecutouts 10, which previously (FIG. 4, 6) formed an opening 26 located atthe left-hand end of the shafts 6 for the downward passage of the dough,now to arrive in the vertical position (FIG. 1) so that this opening 26is closed and instead a similar opening 27 (FIG. 9) located at theright-hand end of the shafts 6 is opened. The two depositing belts 12now move to the right (FIG. 10), the right-hand depositing belt 12, as aresult of its circulatory movement (arrow 7, FIG. 2), depositing thedough strand continuously flowing through the opening 27 to the saiddepositing belt onto the delivery belt 20. As soon as the positionaccording to FIG. 11 is reached, in which the gap 14 formed by the twodepositing belts 12 has reached its right-hand end position in which itlies underneath the opening 27, the position according to FIG. 1 isreached. By means of their timed step-by-step action, the two shafts 6are now again further rotated 90°, whereupon a new dough strand portionis deposited on the left-hand depositing belt 12 in the same way as wasdescribed with reference to FIG. 9. The two depositing belts 12 are thendisplaced to the left (FIG. 11) together, so that the dough strand 24emerging through the opening 27 is gradually deposited on the right-handdepositing belt 12 which continuously deposits it on the delivery belt20 located underneath. As soon as the position according to FIG. 8 isreached, a cycle is completed and a new operating cycle starts.

[0020] As is evident, the width of the gap 14 between the two depositingbelts 12 is at least the same size, preferably larger than the thicknessof the dough strand to be produced. This thickness may be varied bychanging the size of the cutouts 10. This may be effected by replacingthe shafts 6 with shafts 6 having correspondingly larger or smallercutouts 10 or, optionally, also by means of adjustable slides arrangedon the shafts 6 and fixable in the adjusted position. Similarly, thethickness of the dough strand may be varied by increasing or reducingthe period of time that passes until the respective following star arms5 are moved into the closed position. A dough strand havingsubstantially constant thickness may be produced by mutual adaptation ofthese options.

[0021] Schematically represented in FIG. 12 is the aforementioneddischarge of the dough strand 24 from the dough material 28 located inthe receptacle 2. It is apparent that the previously describeddepositing of the dough strand 24 initially takes place in a meandershape, but as a consequence of the operation of the two depositing belts12 the meander shape is transformed into an elongated shape of the doughstrand 24.

1. Apparatus for forming a dough strand from a preferably large-volumedough mixture (28), comprising a receptacle (2) for holding the doughmixture (28), which is provided at the bottom with a discharge opening(4) for the dough, to which two shafts (6) are connected, arranged so asto be fixed parallel to one another and driven in opposite directions ina timed manner for rotary movement in order to effect a downwardmovement of the dough, the said shafts being provided with profilesacting on the dough in the form of an even number of star arms (5) foreach shaft (6), characterised in that the star arms (5) of the shafts(6) in the position directed towards one another block the downward flowof dough therethrough only over the major part of the axial length ofthe shafts (6), the said star arms (5) of each shaft, however, beingprovided at the shaft ends alternately with cutouts (10) for the flow ofthe dough therethrough during pauses in the timed rotary movement of theshafts (6), and in that two depositing belts (12) are arrangedunderneath these shafts (6) in the longitudinal direction of the shafts(6) and spaced apart from one another, which belts are drivable forcirculatory movement in opposite directions and for preferably jointreciprocal displacement in the longitudinal direction thereof. 2.Apparatus according to claim 1, characterised in that a delivery belt(20) driven continuously for circulatory movement is arranged underneaththe two depositing belts (12).
 3. Apparatus according to claim 1 or 2characterised in that each depositing belt (12) is at least as long asthe mutual spacing of the cutouts (10) arranged at the two shaft ends 4.Apparatus according to claim 1, 2 or 3, characterised in that the twodepositing belts (12) lie on the same level and are spaced apart attheir ends directed towards one another to form a gap (14).
 5. Apparatusaccording to one of claims 1 to 4, characterised in that the cutouts(10) of each of two star arms (5) cooperating with one another arearranged such that the two cutouts (10) in each case form a commonopening (26 or 27).
 6. Apparatus according to claim 4, characterised inthat the spacing formed by the gap (14) is at least as large as thethickness of the dough strand (24) to be produced.
 7. Apparatusaccording to one of claims 1 to 6, characterised in that each shaft (6)has four star arms (5).
 8. Apparatus according to one of claims 1 to 7,characterised in that each cutout (10) starts from the edge (11) of thestar arm (5) remote from the axis of the shaft (6).
 9. Apparatusaccording to one of claims 1 to 8, characterised in that the cutouts(10) are rectangular and are each the same size.
 10. Apparatus accordingto one of claims 1 to 9, characterised in that the two shafts (6) aredriven by a common motor (9).
 11. Apparatus according to one of claims 1to 10, characterised in that an individual motor (15) for thecirculatory movement is provided for each depositing belt (12). 12.Apparatus according to one of claims 1 to 11, characterised in that bothdepositing belts (12) are held in a common frame (18) which is movableto and fro by means of a drive (19) in the axial direction of the shafts(6).